Supercritical fluid extraction of forskolin from Coleus forskohlii roots Original Research Article

Forskolin (FSK), a labdane diterpene compound having high nutraceutical and therapeutic activity has been extracted from dried Coleus forskohlii roots using supercritical carbon dioxide (SC-CO2). The solubility parameter of FSK, CO2, and entrainer solvents was calculated and validated with experimental results. Theoretically, pressure and temperature had significant effect on extraction of FSK. A maximum of 50.32% recovery of FSK was obtained after SC-CO2 extraction at 40 °C, 250 bar and extraction time of 60 min. Use of methanol as an entrainer at 20% v/w of dried C. forskohlii roots under optimized conditions improved the recovery of FSK to 74.29%. The recovery of FSK further increased marginally to 77.08% when pre-treated with ultrasonication and commercial enzyme preparation of Stargen® 002 and Accellerase® 1500.